WASHINGTON » President Barack Obama will get a short-term lift for his nominees, judicial and otherwise, but over the immediate horizon, the strong-arm move by Senate Democrats on Thursday to limit filibusters could usher in an era of rank partisan warfare beyond even what Americans have seen in the past five years.

Ultimately, a small group of centrists — Republicans and Democrats — could find the muscle to hold the Senate at bay until bipartisan solutions can be found. But for the foreseeable future, Republicans, wounded and eager to show they have not been stripped of all power, are far more likely to unify against the Democrats who humiliated them in such dramatic fashion.

"This is the most important and most dangerous restructuring of Senate rules since Thomas Jefferson wrote them at the beginning of our country," declared Sen. Lamar Alexander, R-Tenn. "It’s another raw exercise of political power to permit the majority to do whatever it wants whenever it wants to do it."

The decision to press the button on the so-called nuclear option was no doubt cathartic for a Democratic majority driven to distraction by Republican obstructionism. Obama had predicted that his re-election would break the partisan fever gripping Washington, especially since the Tea Party movement swept Republicans to control of the House. It did not.

"Doing nothing was no longer an option," said Sen. Tom Udall of New Mexico, one of a new breed of Democrats who have pressed to reform Senate rules.

The fever is hardly gone, though. The rule change lowered to a simple 51-vote majority the threshold to clear procedural hurdles on the way to the confirmation of judges and executive nominees. But it did nothing to streamline the gantlet that presidential nominees run. Republicans may not be able to muster the votes to block Democrats on procedure, but they can force every nominee to exhaust days of debate between every procedural vote in the Senate book – of which there will be many.

And legislation, at least for now, is still very much subject to the filibuster. On Thursday afternoon, as one Republican after another went to the Senate floor to lament the end of one type of filibuster, they voted against cutting off debate on the annual defense policy bill, a measure that has passed with bipartisan support every year for decades.

"Today’s historic change to Senate rules escalates what is already a hyperpartisan atmosphere in Washington, which is already preventing Congress from addressing our nation’s most significant challenges," said former Sen. Olympia Snowe, a Republican, and former Rep. Dan Glickman, a Democrat, in a statement from the Bipartisan Policy Center.

Republican senators who were willing to team with Democrats on legislation like an immigration overhaul, farm policy and a reauthorization of the Violence Against Women Act will probably think twice going forward.

"We’ll have to see, but I think it was certainly unfortunate," said Sen. Susan Collins, R-Maine, who has often worked with Democrats.

Sen. Mitch McConnell of Kentucky, the Republican leader, made clear that he hoped to exact the ultimate revenge, taking back control of the Senate and using the new rules against the Democrats who made them. "The solution to this problem is at the ballot box," he said. "We look forward to having a great election."

David Axelrod, a former top adviser to Obama, said retaliation by Republicans against the president’s broader agenda would end up hurting them more than Democrats. "If their answer is, ‘Oh yeah, we can make it even worse,’ I think they do that at great risk," Axelrod said. "They have to make a decision about whether they want to be a shrinking, shrieking, blocking party, or if they are going to be a national party."

From the moment Obama took office, the president who proclaimed that there was no red America and blue America, only the United States of America, has strained to maintain some pretense of bipartisanship — through protracted and fruitless efforts to woo Republicans on his economic stimulus plan and health care law, through dinner dates with some handpicked Republican "friends," through the nomination of Chuck Hagel, a former Republican senator, to lead the Defense Department.

In the raucous and dysfunctional House of Representatives, any bill, no matter how inflammatory, has been dubbed bipartisan so long as it attracts a handful of Democratic votes. While Senate leaders have held up for praise any legislation that has secured strong bipartisan majorities — a farm bill, an immigration overhaul, a reauthorization of the Violence Against Women Act — Democrats have seethed as one presidential nominee after another fell to procedural blockades and major initiatives like gun control collapsed when they could not reach the 60-vote threshold.

Then Thursday, before a solemn, almost funereal gathering on the Senate floor, the pretense came to an end.

"It became clear even to reluctant members that their strategy of gridlock helped them more than us, because we are the party that believes government has to be a force for good," said Charles E. Schumer of New York, the third-ranking Senate Democrat.

At the White House, officials from the president down came to the same conclusion.

"Enough is enough," Obama said after the votes in the Senate. "The American people’s business is far too important to keep falling prey day after day to Washington politics."

If Reid or future majority leaders extend the new rules to curb filibusters on legislation, a core group of moderates could emerge with new muscle. The Senate is usually narrowly divided, and it would not take a large coalition in the center to hold partisan legislation hostage to a bipartisan coalition.

Already, a group of former governors, led by Sen. Joe Manchin III, D-W.Va., Alexander and Sen. Tom Carper, D-Del., have begun banding together.

Obama expressed hope that a bipartisan spirit would "have a little more space now." And White House officials said it was still in the interest of Senate Republicans to find a way to legislate, rather than to simply obstruct for the rest of Obama’s term.

For now, with legislative progress in the House all but doomed by Republican opposition, officials said the president could at least get a full team in place so that he can move forward with executive action, when possible, when Republicans block his agenda in Congress.

That’s what Republicans fear.

"This is nothing more than a power grab in order to try to advance the Obama administration’s regulatory agenda," McConnell said.

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Jonathan Weisman, New York Times

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